The present invention relates to a method of measuring a relative dielectric constant of a dielectric substance of powders and, more particularly, a method of measuring a relative dielectric constant of powders capable of measuring a relative dielectric constant of a dielectric substance of powders with high precision even in a high-frequency band in excess of several GHz.
With improvements in the performance of various radio equipments, high-frequency ceramics dielectric substances of higher performance are requested. Normally the ceramics dielectric substances are used in the form of sintered products that are obtained by sintering the powder dielectric substance. Also, the composite dielectric substance in which the powder dielectric substance and the resin, or the like are mixed in various ratios is employed as the circuit parts. As a result, upon developing the high-frequency ceramics dielectric substance, it is necessary and indispensable to measure a relative dielectric constant of the dielectric substance in its powder state as the dielectric property of such dielectric substance.
For example, as disclosed in Japanese Patent No. 3127623, and the like, powders whose relative dielectric constant is to be measured are sealed in the vessel in which a pair of electrodes are arranged to oppose to each other at a predetermined interval, and then the relative dielectric constant of the powders is measured. Then, the relative dielectric constant of a mixed substance consisting of the powders and a liquid is measured by applying a voltage between a pair of electrodes, and then the relative dielectric constant of the powders is calculated based on the measured relative dielectric constant of the mixed substance.
However, in the method of measuring the relative dielectric constant of the powders in the prior art, the presence of the stray capacitance and the stray reactance cannot be ignored when the relative dielectric constant of the powders is to be measured in the high-frequency band in excess of several GHz. As a result, such a problem existed that the resonation of the overall measuring system is caused and thus it is unfeasible to measure the relative dielectric constant of the powders with high precision.